The overall goal of the Genetics, Biomarkers, and Neuropathology Core is to provide resources and expertise to PANUC investigators and other collaborators. This Core will: 1. GENETICS;Provide expert preparation of plasma and DNA from Clinical Core participant blood samples. DNA will be stored and used for genetic analysis by Project 3. Blood samples will be appropriately deposited with the NINDS Genetic Resource Center at the Coriell Institute for distribution to other investigators while insuring proper safeguards. 2. BIOMARKER;Provide analysis of CSF using validated biomarkers, and provide a platform for rapid translation of potential new biomarkers for cognitive impairment in Parkinson's disease discovered in a linked ROI AG033398 (Zhang's project) and Project 3. Plasma obtained in Aim 1 will also be stored as a resource for future biomarker studies. 3. NEUROPATHOLOGY: Provide diagnostic expertise to the Clinical Core by providing family members of the deceased and physicians involved in their care with timely autopsy reports based on the most current standardized diagnostic criteria, and optimally prepare brain donations to advance research in Project 2 and Zhang's project. This Core sen/es several initiatives in the NIH Blueprint. It uses existing NIH resources, contributes essential materials to NIH repositories, and is highly patient-oriented and translational